SILVER may have just become even more precious. The metal packs as much of a punch against cancer cells as a leading chemotherapy drug, and could reduce the negative side effects that accompany such treatment.

Cisplatin, used to treat a range of cancers, contains platinum. The drug is formed from groups of molecules attached to a platinum atom, creating a compound that reacts with DNA in cancer cells. It is the molecules surrounding the metal that determine how reactive the compound is.

Previous studies have hinted that silver compounds could also kill cancer cells. So Charlotte Willans from the University of Leeds, UK, and colleagues subjected silver to the same treatment as platinum to see if they could make an effective cancer drug.